Prefilling Oil Filters & How many Changes until all old oil is gone

I always pre fill the new filter because that is the way I was taught when I was 16 years old. I can't think of any downside to doing it,

There are some premium oil filters out there like the Mobil 1 and Fram Ultra that are rated for up to 20,000 miles. While that seems like stretching it, I had no problem only changing them every other oil change which was 5000 miles for the (synthetic) oil and 10,000 miles on the filter.

My Jaguar takes a top mounted cannister filter and oil changes are done with a Mityvac extracting through the coaxially mounted tube in the oil filler opening. The oil needs to be fairly warm to extract easily. And I sure love using a Mityvac rather than the old fashioned method of doing oil changes.

However the owners manual does have a precaution regarding changing the filter. That is to pour a few ounces of fresh oil down into the filter housing before installing the new filter. This is of course after extracting as much oil as possible with the Mityvac and getting ready to add fresh oil. I presume this is to have the same effect as pre filling a conventional screw on filter. I heed their warning.
 
Back
Top